It was a dark day, indeed, for Windows XP loyalists. On Tuesday, Microsoft finally called it quits with regard to offering support for Windows XP.

For 12 years, Microsoft has provided support for Windows XP. With Microsoft focused squarely on the future, XP does not fit into that vision. Consequently, technical assistance for Windows XP is no longer available, including automatic updates that protect your PC.

“Microsoft has also stopped providing Microsoft Security Essentials for download on Windows XP,” the software giant explains. “If you already have Microsoft Security Essentials installed, you will continue to receive antimalware signature updates for a limited time, but this does not mean that your PC is secure because Microsoft is no longer providing security updates to help protect your PC.”

By Microsoft’s own admission, if you continue to use Windows XP now that support has ended, your computer will still work but it might become more vulnerable to security risks and viruses.

Lastly, Internet Explorer 8 is also no longer supported, so if your Windows XP PC is connected to the Internet and you use Internet Explorer 8 to surf the web, you might be exposing your PC to additional threats.

All told, lingering Windows XP fans are now encouraged to make the dramatic upgrade to Windows 8.1.